Broken in?
Thread Starter
Burning Brakes
Joined: Jul 2000
Posts: 1,162
Likes: 2
From: Beaverton, OR
Broken in?
To add to the saga of my posts . . .
I'm wondering if my engine was broken in when I took these readings at 500 miles:
Cylinder Compression
1 200
2 197
3 210
4 202
5 185
6 197
7 195
8 196
The engine has forged pistons. . . It burned about 2.5 quarts in the first 500 miles. I have another 200 miles on it and it seems like it hasn't burned much if any, but it's hard to say until it goes through at least a quart. I've also been easier on it in the last 200 miles than the first 500.
My oil pressure is through the roof, litterally. My needle is pegged and it only drops when it is fully warmed up and at idle, at which point is usually reads about 40, but likes to jump a lot (something I'm not used to seeing). I do have the fuel filter bypass blocked off, not sure if that matters or not. This "normal" for a high volume pump? The needle is definitely jumpy. I'm tempted to put a normal pump in, but not sure how hard it would be to do . . .
-dath
I'm wondering if my engine was broken in when I took these readings at 500 miles:
Cylinder Compression
1 200
2 197
3 210
4 202
5 185
6 197
7 195
8 196
The engine has forged pistons. . . It burned about 2.5 quarts in the first 500 miles. I have another 200 miles on it and it seems like it hasn't burned much if any, but it's hard to say until it goes through at least a quart. I've also been easier on it in the last 200 miles than the first 500.
My oil pressure is through the roof, litterally. My needle is pegged and it only drops when it is fully warmed up and at idle, at which point is usually reads about 40, but likes to jump a lot (something I'm not used to seeing). I do have the fuel filter bypass blocked off, not sure if that matters or not. This "normal" for a high volume pump? The needle is definitely jumpy. I'm tempted to put a normal pump in, but not sure how hard it would be to do . . .
-dath
Le Mans Master
Joined: Jul 2005
Posts: 5,752
Likes: 4
From: Austin Texas
40 lbs. @ idle is alot on a warmed up engine, but that won't account for the loss of oil...the oil pressure gauge should go up steadily relative to rpm, 'till you reach the max rating of the pump...
Thread Starter
Burning Brakes
Joined: Jul 2000
Posts: 1,162
Likes: 2
From: Beaverton, OR
Yeah, if by steadily, you mean as soon as I blip the throttle off of idle it pegs the needle, it does 
It does seem wickedly high to me.
Anyone have any opinions on if my rings have seated yet or not? Cylinders 3 and 5 have quite a bit of variation from the rest. What has me concerned about that is that one is higher and one is lower. Does compression tend to increase as things seat in? Also, I didn't know to use a non-detergent oil as I wasn't told to do so, so I just used Valvoline 10W30. . . Could be that it is taking a little longer to seat in because of that? I'm thinking I'll check the compression again this weekend as I think I now have about 800 miles on it (thought it was 700 last night, but checked this morning).
It does seem wickedly high to me.Anyone have any opinions on if my rings have seated yet or not? Cylinders 3 and 5 have quite a bit of variation from the rest. What has me concerned about that is that one is higher and one is lower. Does compression tend to increase as things seat in? Also, I didn't know to use a non-detergent oil as I wasn't told to do so, so I just used Valvoline 10W30. . . Could be that it is taking a little longer to seat in because of that? I'm thinking I'll check the compression again this weekend as I think I now have about 800 miles on it (thought it was 700 last night, but checked this morning).
Thread Starter
Burning Brakes
Joined: Jul 2000
Posts: 1,162
Likes: 2
From: Beaverton, OR
Originally Posted by gkull
Just run thinner oil. I used 5W-30 and 10W-30 to keep my oil pressure down.
To much pressure is just working the pump.
To much pressure is just working the pump.
Thread Starter
Burning Brakes
Joined: Jul 2000
Posts: 1,162
Likes: 2
From: Beaverton, OR
Any opinions about the rings being seated? The two numbers outside of the group make me wonder. I'm going to try to get out there today and do another check now that I have about 300 more miles on it. Just have to work up the motivation
-dath
-dath
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Thread Starter
Burning Brakes
Joined: Jul 2000
Posts: 1,162
Likes: 2
From: Beaverton, OR
185 - 210 is close to 12% 
So they are close to the 10% number, but not quite there. I'll recheck them all over again after I retorque the intake which seems to be leaking a little bit. . .
So they are close to the 10% number, but not quite there. I'll recheck them all over again after I retorque the intake which seems to be leaking a little bit. . .
